CENELEC - EN 61158-4-3
Industrial communication networks - Fieldbus specifications - Part 4-3: Data-link layer protocol specification - Type 3 elements
|Publication Date:||1 May 2012|
|ICS Code (Networking):||35.110|
|ICS Code (Data link layer):||35.100.20|
|ICS Code (Industrial process measurement and control):||25.040.40|
The data-link layer provides basic time-critical messaging communications between devices in an automation environment.
This protocol provides communication opportunities to a pre-selected "master" subset of datalink entities in a cyclic asynchronous manner, sequentially to each of those data-link entities. Other data-link entities communicate only as permitted and delegated by those master datalink entities.
For a given master, its communications with other data-link entities can be cyclic, or acyclic with prioritized access, or a combination of the two.
This protocol provides a means of sharing the available communication resources in a fair manner. There are provisions for time synchronization and for isochronous operation.